Improvement in roofing compositions



UNITED STATES PATENT QFFICE.

J OH MODERBY AND AUGUSTUS G. STEVENS, OF Mr NOHESTER, N. H.

IMPROVEMENT IN ROOFING COMPOSITIONS.

Specification forming part of Lettu's Patent No. 152,503, dated June230. 1:74; application filed March 14, 1874.

To allwhom it may concern:

Be it known that we, J OHN MoDERBY and AUGUSTUS G. STEVENS, ofManchester, in the county of Hillsborough and State of New Hampshire,have invented certain Improvements in Roofing Com position, known in themarket as the McDel-by and Stevens Roofing, of which the following is aspecification:

W'e prepare it as follows: WV e take five hundred pounds wood-ashes andtwo thousand pounds coal-ashes, and pass them through a No. 12 wirescreen. With this we then thoroughly mix fifty pounds pipe-clay,pulverized, and thirty pounds of oakum, cut fine, so that the fibers areabout one inch in length. To this mixture, while being constantlystirred by machinery, is added four barrels of coaltar, which rendersthe mass of about the same consistence of glaziers putty. Thiscomposition is then packed in barrels, and sold to the trade, to bespread upon roofs of buildings, previously covered with layers of tarredpaper or felt, by means of a hand-trowel. The addition of the oakmntends by its fibrous nature to bind the cement together, much. as hairis used by plasterers to bind plastering to the wall. lhe addition ofpipe-clay also increases its adhesive properties, so that the directrays of a summers sun do not cause it to run or drip from roofs to whichit is applied.

After our composition is spread upon root's we recommend usuallysprinkling over its surface dry sifted gravel or sand. Experience hasdemonstrated that it will not crack in the cold weather of winter or runor drip in the hottest temperatl'ire 0t suml'ner.

\Ve claim as our invention- The within-1nentioned oon'iposition forroot' ing, consisting of coal and wood ashes, pipeclay, oakum, andcoal-tar, when combined together in about these proportions, and for thepurpose set forth.

JOHN MCDERBY. AUGUSTUS G. STEVENS. XYitnesses:

G. W. WILKINs, R. J. P. GOODWIN.

